Acceptance of surrogate end points in clinical trials supporting approval of drugs for cancer treatment by the Japanese regulatory agency

Trends in oncology drug lags in Japan from 2001 to 2020: A cross-sectional study

Anticancer drugs are essential in the treatment of serious diseases, but their applications are limited by drug lags. This study investigated the characteristics of anticancer drugs approved in Japan over the past 20 years and compared the drug lag trends between Japan and the US. We assessed the changes in drug lag between Japan and the US and the factors affecting the drug lags using publicly available data for anticancer drugs approved in Japan from January 2001 to December 2020. A total of 299 anticancer drugs were approved in Japan in the last 20 years. The approval lag median between the US and Japan was 498 days (16.6 months), peaking in 2002, and decreasing annually thereafter. The minimum approval lag was 173.5 days (5.7 months) in 2018. Multivariate regression analysis revealed that "global simultaneous strategy," "catch-up strategy," and "immunotherapy" are major factors shortening the drug lag. In the past decade, 226 anticancer drugs were approved in Japan. The drug lag for anticancer drugs between Japan and the US peaked in 2002, after which it declined sharply to less than a year. However, the lag was shortest in 2018.

Assessment of Surrogate End Point Trends in Clinical Trials to Approve Oncology Drugs From 2001 to 2020 in Japan

Importance

A surrogate end point (SEP) is an end point used in clinical trials as an alternative for measuring the true clinical benefit. The use of SEPs in trials shortens their duration.

Objectives

To investigate the use of SEPs in clinical trials to support the approval of anticancer drugs and to determine whether confirmatory studies that use overall survival (OS) as an end point are being conducted in Japan.

Design, Setting, and Participants

In this cross-sectional study, drug approvals and background information were obtained from publicly available information, such as the Pharmaceuticals and Medical Devices Agency website, for anticancer drugs approved in Japan from January 2001 to December 2020. Data analysis was performed from September 2021 to March 2022.

Main Outcomes and Measures

Characteristics of approved oncology drugs in Japan, end points for pivotal clinical trials, and outcomes of confirmatory trials using OS as an end point following drug approval.

Results

There were 299 anticancer drugs approved in Japan during the study period. Of these, 142 (47.5%) were molecular-targeted drugs, the most common of which targeted non-small cell lung cancer. There were 111 (37.1%) anticancer drugs with orphan designation. From 2001 to 2005, OS was used as an end point in 1 approval (3.6%); however, from 2006 to 2020, OS was used in 86 approvals (31.7%). Of the 212 anticancer drugs approved on the basis of SEPs, confirmatory studies with OS as the end point were conducted for only 37 approvals (17.5%); for the remaining 175 approvals, studies are under way for 35 approvals (16.5%), were waivered for 75 approvals (35.4%), and were not conducted for 65 approvals (30.7%). Furthermore, in 20 drug approvals (9.4%), the conducted confirmatory studies were not effective in determining the OS, but the drugs were approved following re-examination.

Conclusions and Relevance

The findings of this study suggest that starting from 2005, the use of OS as an end point has increased in studies supporting the approval of anticancer drugs in Japan. However, even after 2005, approximately two-thirds of these approvals were SEP based. Postmarketing surveillance studies of the true end points are necessary to validate the use of SEPs.

Correlation of Anticancer Drug Prices with Outcomes of Overall Survival and Progression-Free Survival in Clinical Trials in Japan

Drug pricing methods vary extensively across countries. Japan calculates drug prices using cost accounting and based on the efficacy of similar drugs. This study investigated the relationship between drug prices and their clinical efficacy and usefulness using public information on anticancer drugs reimbursed by the National Health Insurance price listing between January 2009 and March 2020. We investigated drug characteristics, prices, and clinical benefits based on overall survival (OS) and progression-free survival (PFS). Eighty anticancer drugs were approved in Japan during the study period. The largest number (28 drugs, 35.0%) was approved based on PFS, 18 (22.5%) were approved based on OS, and 13 (16.3%) based on the response rate. The mean (±SD) drug price was JPY 88,416.2 (±148,974.7), while the median drug price (with quartiles) was JPY 21,694 (JPY 4855.0-JPY 93,396.8). Drug prices were significantly higher for PFS than for OS, while cost index-the drug price to extend PFS or OS by one day-did not differ significantly between PFS and OS. The relationship between the 46 drugs approved based on OS or PFS and their prices was examined. A correlation was found between drug prices and their clinical usefulness in terms of OS but not PFS.

Relationships between developmental strategies for additional indications and price revisions for anticancer drugs in Japan

Background

The relationships between developmental strategies for additional indications and drug price revisions have not been thoroughly studied. Here, we investigated the price revisions for anticancer drugs approved in Japan.

Methods

The study was based on published information on anticancer drugs approved between January 2009 and March 2020 in Japan. We investigated the relationships between the pharmacological and regulatory characteristics of anticancer drugs and occurrence/non-occurrence of the Japanese National Health Insurance (NHI) price revisions.

Results

Eighty-one new anticancer drugs were given NHI price listings during the survey. On April 1, 2020, the prices of 23 anticancer drugs had been revised from the initial pricing, the prices were reduced for 21 drugs (91.3%). Several parameters showed the relationships between drug characteristics and NHI price revisions. The achievement of additional indications and compound type were identified as explanatory factors for these relationships. Additional indication profiles were defined to assess the relationships between the methods for additional indication achievement and price revisions. When the type of additional indication was “Expansion”, the percentage of drugs received NHI price revisions was the highest (P<0.001).

Conclusions

NHI price revision was significantly related to the achievement of additional indications and compound type. The strategy for additional indications was found to affect the occurrence/non-occurrence of NHI price revisions.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12913-021-07360-w.

Reforms of regulatory pathways for approval of new antineoplastic drugs in Japan from 2004 to 2019 and accompanying changes in pivotal clinical trial designs

Background The Japanese Pharmaceuticals and Medical Devices Agency (PMDA) was established in 2004. Since then, various pieces of legislation, notices, and guidelines have been issued, and the regulatory approval pathways for domestic drugs have been diversified. However, the effects of these measures have not been fully examined. We examined the impact of these measures on the approval of antineoplastic drugs and the design of pivotal clinical trials for efficacy assessment by the PMDA. Methods We collected data on the antineoplastic drugs approved by the PMDA in fiscal years 2004-2019. We extracted the approval review pathways and the pivotal clinical trial designs from the PMDA review reports, and analyzed them to identify patterns. Results In total, 387 indications in oncology were approved by the PMDA in fiscal years 2004-2019, or 365 indications excluding multiple regulatory pathways. The number of approved indications generally increased year on year (p < 0.001). The largest number of approved indications was under the Orphan Drug Designation (31%, 114/365) and this continues to increase (p < 0.001). In the 288 indications for which clinical trial data were submitted for review, the pivotal clinical trial designs changed significantly (p < 0.001) after the guideline on clinical evaluation for antineoplastic drugs was revised in 2006. Conclusion The number of indications in oncology approved by the PMDA has been increasing over the past 16 years, alongside changes in regulatory pathways. The 2006 guideline on clinical evaluation had a particular impact on pivotal clinical trial designs.

Searching for potential surrogate endpoints of overall survival in clinical trials for patients with prostate cancer

BACKGROUND

The purpose of this study was to investigate the correlation between overall survival (OS) and other clinical outcomes in patients with prostate cancer. Further, we conducted subgroup analysis in the correlation of OS.

AIM

This study intended to investigate potential surrogate endpoints of OS for prostate cancer by examining the correlation between OS and the other endpoints.

METHODS

We performed a systematic review through a literature search by computer-based searches of the Medline database (January 1965 and May 2014).

RESULTS

The contents of 115 studies with endpoint as OS were analyzed in our study. Our results showed that 47.8% (55/115) of the studies used progression-free survival as an endpoint besides OS, followed by time to progression (43.5% [50/115]) and PSA response (40.9% [47/115]). Also, the relationship between OS and each surrogate endpoint was examined using the hazard ratio (HR) by a Bayesian hybrid model for random effect multivariate meta-analysis. Our results showed that the endpoint that had the highest correlation with OS was progression-free survival (PFS) with an estimated marginal correlation of 0.939 (95%CI: 0.900, 0.967). Furthermore, our stratified analysis identified PFS in castration-resistant prostate cancer patients (0.937), in sensitive patients (0.932), in none of chemotherapy patients (0.929), in first line of the chemotherapy (0.948), in patients who received no Docetaxel previously (0.942), in both symptomatic and asymptomatic patients (0.950), in patients who received only chemotherapy (0.956), and in phase III (0.960), time to progression (TTP) in castration-resistant prostate cancer (CRPC) patients (0.942), in metastasis patients (0.948), in both symptomatic and asymptomatic patients (0.953), in patients who received only chemotherapy (0.938), and in Phase III (0.927) as endpoints, which showed a lower limit for 95% CI of estimated marginal correlation ≥0.850 with overall survival.

CONCLUSIONS

Our study suggests that PFS is a potential surrogate endpoint of OS in clinical trials for patients with prostate cancer. It also suggests potential surrogate endpoints for CRPC and locally advanced prostate cancer.

Unique characteristics of regulatory approval and pivotal studies of orphan anticancer drugs in Japan

The approval of orphan anticancer drugs has increased, with the number exceeding that of non-orphan drugs in Japan in recent years. Although orphan anticancer drugs may have unique characteristics due to their rarity, these have not been fully characterized. We investigated anticancer drugs approved in Japan between April 2004 and November 2017 to reveal the characteristics of regulatory approval and pivotal studies on orphan anticancer drugs compared to non-orphan drugs. The median regulatory review time and number of patients in pivotal studies on orphan anticancer drugs (281.0 days [interquartile range, 263.3-336.0]; 222.5 patients [66.0-454.3]) were significantly lower than those on non-orphan drugs (353.0 days [277.0-535.5]; 521.0 patients [303.5-814.5], respectively) (P < 0.001). Phase II, non-randomized and non-controlled designs were more frequently used in pivotal studies on orphan anticancer drugs (45.9%, 41.9% and 43.2%) than non-orphan drugs (17.2%, 14.1% and 14.1%, respectively). Response rate was more commonly used as a primary endpoint in pivotal studies on orphan anticancer drugs (48.6%) than non-orphan drugs (17.2%). Indications limited by molecular features, second or later treatment line, and accelerated approval in the United States were associated with the use of response rate in orphan anticancer drug studies. In conclusion, we demonstrated that orphan anticancer drugs in Japan have unique characteristics compared to non-orphan drugs: shorter regulatory review and pivotal studies frequently using phase II, non-randomized, or non-controlled designs and response rate as a primary endpoint, with fewer patients.

Characteristics of clinical trials in rare vs. common diseases: A register-based Latvian study

Background

Conducting clinical studies in small populations may be very challenging; therefore quality of clinical evidence may differ between rare and non-rare disease therapies.

Objective

This register-based study aims to evaluate the characteristics of clinical trials in rare diseases conducted in Latvia and compare them with clinical trials in more common conditions.

Methods

The EU Clinical Trials Register (clinicaltrialsregister.eu) was used to identify interventional clinical trials related to rare diseases (n = 51) and to compose a control group of clinical trials in non-rare diseases (n = 102) for further comparison of the trial characteristics.

Results

We found no significant difference in the use of overall survival as a primary endpoint in clinical trials between rare and non-rare diseases (9.8% vs. 13.7%, respectively). However, clinical trials in rare diseases were less likely to be randomized controlled trials (62.7% vs. 83.3%). Rare and non-rare disease clinical trials varied in masking, with rare disease trials less likely to be double blind (45.1% vs. 63.7%). Active comparators were less frequently used in rare disease trials (36.4% vs. 58.8% of controlled trials). Clinical trials in rare diseases enrolled fewer participants than those in non-rare diseases: in Latvia (mean 18.3 vs. 40.2 subjects, respectively), in the European Economic Area (mean 181.0 vs. 626.9 subjects), and in the whole clinical trial (mean 335.8 vs. 1406.3 subjects). Although, we found no significant difference in trial duration between the groups (mean 38.3 vs. 36.4 months).

Conclusions

The current study confirms that clinical trials in rare diseases vary from those in non-rare conditions, with notable differences in enrollment, randomization, masking, and the use of active comparators. However, we found no significant difference in trial duration and the use of overall survival as a primary endpoint.

The Landscape of Clinical Trials Evaluating the Theranostic Role of PET Imaging in Oncology: Insights from an Analysis of ClinicalTrials.gov Database

In the war on cancer marked by personalized medicine, positron emission tomography (PET)-based theranostic strategy is playing an increasingly important role. Well-designed clinical trials are of great significance for validating the PET applications and ensuring evidence-based cancer care. This study aimed to provide a comprehensive landscape of the characteristics of PET clinical trials using the substantial resource of ClinicalTrials.gov database. We identified 25,599 oncology trials registered with ClinicalTrials.gov in the last ten-year period (October 2005-September 2015). They were systematically reviewed to validate classification into 519 PET trials and 25,080 other oncology trials used for comparison. We found that PET trials were predominantly phase 1-2 studies (86.2%) and were more likely to be single-arm (78.9% vs. 57.9%, P <0.001) using non-randomized assignment (90.1% vs. 66.7%, P <0.001) than other oncology trials. Furthermore, PET trials were small in scale, generally enrolling fewer than 100 participants (20.3% vs. 25.7% for other oncology trials, P = 0.014), which might be too small to detect a significant theranostic effect. The funding support from industry or National Institutes of Health shrunk over time (both decreased by about 5%), and PET trials were more likely to be conducted in only one region lacking international collaboration (97.0% vs. 89.3% for other oncology trials, P <0.001). These findings raise concerns that clinical trials evaluating PET imaging in oncology are not receiving the attention or efforts necessary to generate high-quality evidence. Advancing the clinical application of PET imaging will require a concerted effort to improve the quality of trials.

Clinical trial designs to obtain marketing authorization of drugs for haematological malignancy in Japan, the EU and the US

Differences in regulatory actions between Japan, the European Union (EU) and the United States (US) regarding the approval date and primary endpoints of pivotal trials have never been analysed comprehensively. This study aimed to examine such differences in haematological malignancy indications not only in applications for new molecular entity agents but also in supplemental applications for additional indications. A total of 101 haematological malignancy indications were examined for 58 drugs. Only 30 indications were approved by the regulatory agencies of all three regions with 25, 9 and 67 indications being first approved in Japan, the EU and the US, respectively. Regarding the 18 indications approved only in the US, 13 were approved based on results of single-arm trials. The approval of all nine indications approved first in the EU was based on results of comparative trials. The primary endpoints were different between the EU and the US in 4 of 49 indications approved by both regulatory agencies, all of which were approved earlier in the US than in the EU. This analysis shows that the US Food and Drug Administration has taken the most active attitude to acceptance of surrogate endpoints in single-arm trials. Therefore, not only shorter review time but also this attitude may lead to earlier approval in US.

Covalently bonded double-charged ionic liquid on magnetic graphene oxide as a novel, efficient, magnetically separable and reusable sorbent for extraction of heavy metals from medicine capsules

Development of a new SPE sorbent with a chemically bonded double-charged ionic liquid on magnetic graphene oxide to solve the disadvantages of ionic liquid based SPE methods.

Recent trends for drug lag in clinical development of oncology drugs in Japan: does the oncology drug lag still exist in Japan?

BACKGROUND

This study exhaustively and historically investigated the status of drug lag for oncology drugs approved in Japan.

METHODS

We comprehensively investigated oncology drugs approved in Japan between April 2001 and July 2014, using publicly available information. We also examined changes in the status of drug lag between Japan and the United States, as well as factors influencing drug lag.

RESULTS

This study included 120 applications for approval of oncology drugs in Japan. The median difference over a 13-year period in the approval date between the United States and Japan was 875 days (29.2 months). This figure peaked in 2002, and showed a tendency to decline gradually each year thereafter. In 2014, the median approval lag was 281 days (9.4 months). Multiple regression analysis identified the following potential factors that reduce drug lag: "Japan's participation in global clinical trials"; "bridging strategies"; "designation of priority review in Japan"; and "molecularly targeted drugs".

CONCLUSIONS

From 2001 to 2014, molecularly targeted drugs emerged as the predominant oncology drug, and the method of development has changed from full development in Japan or bridging strategy to global simultaneous development by Japan's taking part in global clinical trials. In line with these changes, the drug lag between the United States and Japan has significantly reduced to less than 1 year.

Regulatory review time for approval of oncology drugs in Japan between 2001 and 2014. Considerations of changes, factors that affect review time, and difference with the United States

In this study, we comprehensively and historically studied the review time of oncology drugs approved by the regulatory authorities in Japan with publicly available information. A total of 120 applications of oncology drugs were approved in Japan between April 2001 and July 2014. The review time peaked with 732.0 days (24.4 months) in 2005, and showed a tendency to decline gradually each year thereafter. After 2012, a significant reduction of the review time was seen in comparison to the median of 13-year median time. In addition, we compared the review time with that in the United States. The median review time lag with the United States was significantly peaked in 2005. After 2005, the review time lag with the FDA has decreased, but lag did not significantly reduce by 2014. We also examined factors influencing the review time in Japan with multiple regression analysis. It was found that the factors related to a use of overseas data and expedited program for accelerating the reviews influenced the direction of shortening the review time. We consider that regulatory authorities in Japan need to keep making efforts to reduce the review time further and eliminate the review time lag with the United States.